He will benefit from a re-evaluation for his BPH and bladder irritability both. Needs full investigation including DRE ,CBC PSA KFT urine RM and Culture and sensitivity HBAIC, USG KUB, PVR, Uroflowmetry, Urodynamic study and decision for Medical or Surgical treatment thereafter. Urimax
D with Solifenacin
for sometime with a small course of antibiotic and bladder training and diabetic control is one option but after full urological evaluation.